The base scanline class containing a row of facade::png::PixelSpan of the given pixel type. More...

#include <png.hpp>

Public Types
using	Span = PixelSpan< PixelType >
	The pixel span this scanline holds.

Public Member Functions
	ScanlineBase ()

	ScanlineBase (std::uint8_t filter_type, std::size_t width)

	ScanlineBase (std::uint8_t filter_type, std::vector< Span > pixel_data)

	ScanlineBase (const ScanlineBase &other)

Pixel	operator[] (std::size_t index) const
	Syntactic sugar for getting a facade::png::Pixel variant.

std::uint8_t	filter_type () const
	Get the filter type of this scanline.

void	set_filter_type (std::uint8_t filter_type)
	Set the filter type of this scanline.

__attribute__((used)) const std std::size_t	pixel_span () const
	Return a const reference to the underlying pixel data array.

std::size_t	pixel_width () const
	Return the size, in samples, of the given scanline.

Span &	get_span (std::size_t index)
	Get the facade::png::PixelSpan reference at the given index.

const Span &	get_span (std::size_t index) const
	Get the const facade::png::PixelSpan reference at the given index.

void	set_span (const Span &span, std::size_t index)
	Set the facade::png::PixelSpan object at the given index.

Pixel	get_pixel (std::size_t index) const
	Get the pixel at the given index.

void	set_pixel (const Pixel &pixel, std::size_t index)
	Set the pixel at the given index.

std::vector< std::uint8_t >	to_raw () const
	Convert this scanline to raw byte form.

ScanlineBase	reconstruct (std::optional< ScanlineBase > previous) const
	Reconstruct the scanline based on its filter value.

ScanlineBase	filter (std::optional< ScanlineBase > previous) const
	Calculate all filters and determine the best compressed filter among them.

ScanlineBase	filter (FilterType filter_type, std::optional< ScanlineBase > previous) const
	Calculate the given filter type on this scanline.

Static Public Member Functions
static ScanlineBase	read_line (const std::vector< std::uint8_t > &raw_data, std::size_t offset, std::size_t width)
	Create a scanline object from raw data at the given data offset.

static std::vector< ScanlineBase >	from_raw (const Header &header, const std::vector< std::uint8_t > &raw_data)
	Collect a vector of scanlines from the given raw data.

Detailed Description

template<typename PixelType>
class facade::png::ScanlineBase< PixelType >

The base scanline class containing a row of facade::png::PixelSpan of the given pixel type.

Template Parameters

PixelType The pixel type this scanline holds.

Member Typedef Documentation

◆ Span

template<typename PixelType >

using facade::png::ScanlineBase< PixelType >::Span = PixelSpan<PixelType>

The pixel span this scanline holds.

Constructor & Destructor Documentation

◆ ScanlineBase() [1/4]

template<typename PixelType >

facade::png::ScanlineBase< PixelType >::ScanlineBase ( )

inline

◆ ScanlineBase() [2/4]

template<typename PixelType >

facade::png::ScanlineBase< PixelType >::ScanlineBase	(	std::uint8_t	filter_type,
		std::size_t	width
	)

inline

◆ ScanlineBase() [3/4]

template<typename PixelType >

facade::png::ScanlineBase< PixelType >::ScanlineBase	(	std::uint8_t	filter_type,
		std::vector< Span >	pixel_data
	)

inline

◆ ScanlineBase() [4/4]

template<typename PixelType >

facade::png::ScanlineBase< PixelType >::ScanlineBase ( const ScanlineBase< PixelType > & other )

inline

Member Function Documentation

◆ filter() [1/2]

template<typename PixelType >

ScanlineBase facade::png::ScanlineBase< PixelType >::filter	(	FilterType	filter_type,
		std::optional< ScanlineBase< PixelType > >	previous
	)		const

Calculate the given filter type on this scanline.

Parameters

filter_type	The facade::png::FilterType to assign on the scanline.
previous	The previous scanline that is sometimes necessary for filtering. Typically the previous scanline if y > 0.

Returns: The filtered scanline result.

Exceptions

facade::exception::AlreadyFiltered
facade::exception::ScanlineMismatch
facade::exception::NoPixels
facade::exception::InvalidFilterType

◆ filter() [2/2]

template<typename PixelType >

ScanlineBase facade::png::ScanlineBase< PixelType >::filter ( std::optional< ScanlineBase< PixelType > > previous ) const

Calculate all filters and determine the best compressed filter among them.

Returns: The newly filtered scanline.

Parameters

previous The previous scanline, if any. This is sometimes necessary for reconstruction procedures.

See also: facade::png::ScanlineBase::filter(std::uint8_t,std::optional<facade::png::ScanlineBase<PixelType>>)

◆ filter_type()

template<typename PixelType >

std::uint8_t ScanlineBase::filter_type

Get the filter type of this scanline.

◆ from_raw()

template<typename PixelType >

std::vector< ScanlineBase< PixelType > > ScanlineBase::from_raw	(	const Header &	header,
		const std::vector< std::uint8_t > &	raw_data
	)

static

Collect a vector of scanlines from the given raw data.

Parameters

header	The header of the given image to collect scanlines from.
raw_data	The raw pixel data from the uncompressed `IDAT` chunks.

Returns: A vector of scanlines of the given scanline type.

Exceptions

facade::exception::PixelMismatch
facade::exception::OutOfBounds

◆ get_pixel()

template<typename PixelType >

Pixel ScanlineBase::get_pixel ( std::size_t index ) const

Get the pixel at the given index.

Index, in this case, is bound by the value returned by facade::png::Header::width.

Exceptions

facade::exception::OutOfBounds

◆ get_span() [1/2]

template<typename PixelType >

Span & facade::png::ScanlineBase< PixelType >::get_span ( std::size_t index )

Get the facade::png::PixelSpan reference at the given index.

Index, in this case, is bound by facade::png::ScanlineBase::pixel_span.

Exceptions

facade::exception::OutOfBounds

◆ get_span() [2/2]

template<typename PixelType >

const ScanlineBase< PixelType >::Span & ScanlineBase::get_span ( std::size_t index ) const

Get the const facade::png::PixelSpan reference at the given index.

Index, in this case, is bound by facade::png::ScanlineBase::pixel_span.

Exceptions

facade::exception::OutOfBounds

◆ operator[]()

template<typename PixelType >

Pixel ScanlineBase::operator[] ( std::size_t index ) const

Syntactic sugar for getting a facade::png::Pixel variant.

See also: facade::png::ScanlineBase::get_pixel

◆ pixel_span()

template<typename PixelType >

__attribute__((used)) const std std::size_t facade::png::ScanlineBase< PixelType >::pixel_span ( ) const

Return a const reference to the underlying pixel data array.

Return the size, in terms of pixel span objects, of the underlying scanline.

Warning: This is not always equivalent to facade::png::Header::width– sometimes it's less than that, due to pixel types that go below 8 bits.

See also: facade::png::ScanlineBase::pixel_width

◆ pixel_width()

template<typename PixelType >

std::size_t facade::png::ScanlineBase< PixelType >::pixel_width ( ) const

Return the size, in samples, of the given scanline.

Warning: This is not always equivalent to facade::png::Header::width– sometimes it's more than that, due to padding issues with samples less than 8 bits. You should know that this returns what the scanline is capable of holding, and not necessarily so much what it is holding.

◆ read_line()

template<typename PixelType >

ScanlineBase< PixelType > ScanlineBase::read_line	(	const std::vector< std::uint8_t > &	raw_data,
		std::size_t	offset,
		std::size_t	width
	)

static

Create a scanline object from raw data at the given data offset.

Parameters

raw_data	The raw data byte vector to read from.
offset	The offset to begin reading the scanline.
width	The width of the scanline.

Returns: The parsed scanline from the raw data.

Exceptions

facade::exception::OutOfBounds

◆ reconstruct()

template<typename PixelType >

ScanlineBase< PixelType > ScanlineBase::reconstruct ( std::optional< ScanlineBase< PixelType > > previous ) const

Reconstruct the scanline based on its filter value.

This essentially performs the inverse of what the facade::png::ScanlineBase::filter functions do.

Parameters

previous The previous scanline, if any. This is sometimes necessary for reconstruction procedures.

Returns: The reconstructed scanline.

Exceptions

facade::exception::ScanlineMismatch
facade::exception::NoPixels
facade::exception::InvalidFilterType

◆ set_filter_type()

template<typename PixelType >

void ScanlineBase::set_filter_type ( std::uint8_t filter_type )

Set the filter type of this scanline.

◆ set_pixel()

template<typename PixelType >

void ScanlineBase::set_pixel	(	const Pixel &	pixel,
		std::size_t	index
	)

Set the pixel at the given index.

Index, in this case, is bound by the value returned by facade::png::Header::width.

Exceptions

facade::exception::OutOfBounds

◆ set_span()

template<typename PixelType >

void ScanlineBase::set_span	(	const Span &	span,
		std::size_t	index
	)

Set the facade::png::PixelSpan object at the given index.

Index, in this case, is bound by facade::png::ScanlineBase::pixel_span.

Parameters

span	The pixel span to set.
index	The index of the span to set it to.

Exceptions

facade::exception::OutOfBounds

◆ to_raw()

template<typename PixelType >

std::vector< std::uint8_t > ScanlineBase::to_raw

Convert this scanline to raw byte form.

The documentation for this class was generated from the following files:

include/facade/png.hpp
src/png.cpp

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Typedef Documentation

◆ Span

Constructor & Destructor Documentation

◆ ScanlineBase() [1/4]

◆ ScanlineBase() [2/4]

◆ ScanlineBase() [3/4]

◆ ScanlineBase() [4/4]

Member Function Documentation

◆ filter() [1/2]

◆ filter() [2/2]

◆ filter_type()

◆ from_raw()

◆ get_pixel()

◆ get_span() [1/2]

◆ get_span() [2/2]

◆ operator[]()

◆ pixel_span()

◆ pixel_width()

◆ read_line()

◆ reconstruct()

◆ set_filter_type()

◆ set_pixel()

◆ set_span()

◆ to_raw()